Any one Running an after market Exhaust manifold?

[driftkid83]

I was just curious if any one was running an after market exhaust manifold on your Rb20? and if so did you notice any power gains or difference in the exhaust note?

[TheRBguy]

I just bought an ebay manifold i am wondering the same thing.

[driftkid83]

I have one aswell, but my motor is already in and was wondering if it was worth all the effort.

[StricNyne]

not worth it at all, the hp restriction on ANY RB motor is pretty much the OEM turbo, you can even find a couple bolt on solutions (bolt onto manifold only) that use stock exh manifold and make a decent amount of HP. Now if u change the manifold and turbo than yes you will make more power, but the main reason is better fitment. I think someone on here managed to get a holset to bolt up to their stock manifold which if possible i would of done and saved a grip on my turbo setup.

[Yellow4g63]

Yeah don't bother with a different manifold and keeping the stock turbo. The stocker sucks big time, small motor needs more boost but if u go past 13psi for extended periods the stock turbo will just come apart. Different manifold with bigger turbo or bigger turbo on stock manifold and mod for external gate. Bigger injectors too RB20's only come with 270's . I have yet to drive my RB20 on the street, at this point it's just a dyno queen lol.

[driftkid83]

Well cefy motor came with an rb25 turbo.. would it be worth it then, the only thing i really want to do is change that crappy dump pipe but not sure where to get one that will fit. Any suggestions?

[StricNyne]

my original dp was the oem dump, with flange cut off and 3in pipe welded on and it kicked a**, and rb25 stock turbo sucks, honestly save the money i mean if you really want research the bolt on options to the rb25 stock manifold, than go from there, if u get some extravannt manifold and bolt stock turbo your paying money for custom intake pipine, charge piping, and downpipe for literally almost miniscule hp gain

[TheRBguy]

I didnt buy my ebay manifold thinking i was gunna get more power i bought it because my stock one was warped terrible and leaked really bad and i just wanted one to fix that problem for cheap.

[StricNyne]

lol if u lived local i would of gave you a manifold hahaha

[driftkid83]

My rb20 came with an rb25 turbo already bolted to, so its not like i paid extra for it. I just hate the look and i'm sure it doesn't help exhaust flow any to have the stock dump pipe as apposed to an after market one that has better flow for the wastegate.

[Carl H]

stock turbo elbow is a huge restriction, changing that out to an aftermarket one will free up some power.
plenty of people have made good power on stock manifold with a big turbo but as mentioned before the manifold isnt the restriction...the turbo is.

[SkylineFreak]

Anybody know if the ebay manifolds that are the exact same style as the stock rb20,25 manifolds are any better in terms of quicker spool up being that they seem to look a lot more free flowing than the factory ones???

[driftkid83]

They definitely look like they do! But looks can be deceiving. I am curious as well.

[SkylineFreak]

Well for the price of one of those ebay manifolds and the time it takes to slap one one it must be worth doing even if if there isn't too much if a change in spool up or even power. They definitely look Sick!

[TheRBguy]

I can tell you they need port matched because they are not even close and the welds inside are absoultely terrible doesnt look like they grinded them at all and you cant get to them with a die grinder.

[StricNyne]

i saw one of the ebay ones that needed to be modofied to work but i never seen the aftermath

[driftkid83]

I've had the same experience with poor workmanship but the ones I bought were not the same ones I ordered. They had a slight difference in design and were still side mount T3 flange but clearly paid more attention to detail as far as the welds and the grinding goes. I guess I was pleasantly surprised. I'll see if I can post a picture to show you what I mean.